"Gosh! I'd like to try it once," said Frank, longingly.
"If you'd really like to try it so much, I don't know but what I can arrange it for you," said the observer slowly. "The trouble is, though, that I can take only two of you, because I have only two extra parachutes."
"We're not apt to need them, are we?" asked Frank.
"Oh, of course, the chances are that we won't, seeing that we won't be attacked now by a hostile machine, as we would likely have been a few months ago," responded the other. "Just the same, it's always possible for accidents to happen, and so I'll have to limit it to two passengers, although I'd like to take you all up."
"You and Bart go, Frank," said Billy. "Tom and I will come around some other time, and then maybe we'll get a chance."
"Well, if you and Tom don't mind, I guess we will," said Frank, and with the words he and Bart stepped into the car of the balloon, followed by the observer.
"I'm afraid you'll find it rather tame," said the latter. "It's not nearly as exciting as you might think when looking at it from the ground."
By this time the balloon was fully inflated, and the observer gave the sign to the man in charge of the windlass to let the big gas bag rise. The windlass man released the brake on the big drum, and the balloon shot upward with a speed that took the breath away from the two passengers. Up they shot until they had attained an altitude of about five hundred feet, after which the windlass man checked their further progress.
The boys exclaimed aloud over the wonderful sight that met their eyes. Mile upon mile the smiling Rhine countryside stretched away on every side. The picturesque Rhine, bordered by its ruined castles, was visible for many miles.
"Isn't that a wonderful sight?" demanded Bart. "Why, from up here it seems as though we should almost be able to see Berlin."